Hell Forge Cost

I have been writing rather lenthy blogs, so I thought I will write a short one this time.
In the game, you can hell forge an item. Official Description ::

The Hell Forge contains the fire of hell itself. Known to contain great power, the fires of hell can be used to unlease the true potential of any item, increasing its statistics permanently (except for hourly 'Gain' stats). Each time you use the forge on an item to increase its forge level (see the guide below) costs 2 FallenSword Points plus an amount of gold depending on the items level.

Now, the question to answer in this blog is, what is that amount of gold?
The gold required for the first forge is [Item level] * 150 gold, subjected to a minimum [Item level] of 50. That is, all items below level 50 are treated as level 50 for the purpose of computing hell forge cost. The gold for subsequent forge is double that of the previous.

I have also written a script to compute the cost, and it can be found here ::
http://sisland83.bravehost.com/forgecost.html